#region Using Directives and Copyright Notice

// Copyright (c) 2007-2010, Computer Consultancy Pty Ltd
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//     * Neither the name of the Computer Consultancy Pty Ltd nor the
//       names of its contributors may be used to endorse or promote products
//       derived from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
// ARE DISCLAIMED. IN NO EVENT SHALL COMPUTER CONSULTANCY PTY LTD BE LIABLE 
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
// DAMAGE.

using System;
using System.Collections.Generic;
using System.Text;

using Interlace.Binding.Views;

#endregion

namespace Interlace.Binding.Utilities
{
    public class BindableOr
    {
        List<BindableLogicInput> _inputs;
        Binder _binder;

        bool _default = false;

        bool _currentValue;

        public BindableOr()
        {
            _inputs = new List<BindableLogicInput>();
            _currentValue = CalculatedOutput;
            _binder = new Binder(this);
        }

        public Binder Binder
        { 	 
            get { return _binder; }
        }

        public void AddBinding(BinderViewBase view)
        {
            _binder.AddBinding("Output", view);
        }

        public void AddBinding(BinderViewBase view, ViewConverterBase converter)
        {
            _binder.AddBinding("Output", view, converter);
        }

        public BinderViewBase CreateInput()
        {
            BindableLogicInput input = new BindableLogicInput();

            _inputs.Add(input);

            input.ValueChanged += new EventHandler(input_ValueChanged);

            UpdateValueIfRequired();

            return new PropertyView(input, "Value", true, true);
        }

        void UpdateValueIfRequired()
        {
            if (CalculatedOutput != _currentValue)
            {
                _currentValue = CalculatedOutput;

                if (OutputChanged != null) OutputChanged(this, EventArgs.Empty);
            }
        }

        void input_ValueChanged(object sender, EventArgs e)
        {
            UpdateValueIfRequired();
        }

        bool CalculatedOutput
        {
            get
            {
                if (_inputs.Count == 0) return _default;

                foreach (BindableLogicInput input in _inputs)
                {
                    if (input.Value) return true;
                }

                return false;
            }
        }

        public event EventHandler OutputChanged;

        public bool Output
        {
            get 
            {
                return _currentValue;
            }
        }
    }
}
